1. Field of the Invention
The present invention relates to photographic cameras of the type employing an elongated film strip supplied in a film cassette and, more particularly, to apparatus for facilitating the loading of an elongated filmstrip in a camera.
2. Description Relative to the Prior Art
To load most 35 mm cameras, the camera operator must insert a film cassette into a film supply chamber, pull the film leader out of the cassette, position the film leader along film guide rails that cooperate with other camera structure to define a film passageway extending between the film supply chamber and a film take-up chamber and manually attach the end of the film leader to a film take-up spool. One problem frequently encountered during this portion of the film loading procedure is that the take-up spool slot or other mechanism for attaching the film to the take-up spool is not oriented in a convenient position for film leader attachment. This problem can be overcome by manually indexing the take-up spool to a proper orientation, but such an operation is time consuming and requires both visual observation and operator dexterity.
If the film leader can be attached positively to the take-up spool without creating film slack in the film passageway, there is no need for the camera operator to wind the film around the take-up spool before closing the camera cover door. However, if there is film slack, the camera operator must wind a short length of film manually onto the take-up spool to prevent buckling or misalignment of the film in the film passageway when the cover door is closed. This procedure is also time consuming and with an inexperienced operator may result in the winding of sufficient film onto the take-up spool so that one or more exposure frames are lost.
One solution to the problem of properly orienting the take-up spool for attachment of the film leader is suggested by U.S. Pat. No. 3,470,801. At the end of the film rewind operation, a detent arrangement arrests the take-up spool in a position such that, upon opening of the camera cover door, a film insertion slot provided in the take-up spool is substantially parallel to the film guide rails.
One solution to the problem of film slack removal is shown in U.S. Pat. No. 3,481,260 wherein an auxiliary film winding mechanism interconnects the camera cover door and the take-up spool and rotates the take-up spool to wind film thereon in response to the closing of the cover door.
The disadvantage of the apparatus disclosed in each of the aforementioned two patents is that they are single purpose mechanisms. That is to say, such apparatus can be operated to eliminate one film loading problem (either orientation of the take-up spool or removal of film slack), but neither apparatus alone can be operated to eliminate both film loading problems.
U.S. Pat. No. 1,947,483 discloses a folding camera adapted for use with a specially constructed, two-part roll full magazine. This film magazine is adapted to be received in the camera by a pair of movably mounted devices that are interconnected with the cover door. When the cover door is closed, the holding devices separate the two magazine parts so as to stretch the film contained therein across the camera exposure frame. When the cover door is opened, the holding devices reunite the two magazine parts in a light-tight manner in preparation for removal from the camera. While the apparatus of U.S. Pat. No. 1,947,483 avoids both of the previously mentioned film loading problems, it suffers the disadvantages of (1) requiring an unorthodox loading procedure, (2) using a specially constructed film magazine that (3) can be used only with cameras specifically designed for use therewith.